placebo effect

There's a new Radio Lab available. It tells the story of how the placebo effect works, from shamans to depression to parkinsons disease. Apparently, 25% of the time, the placebo effect works on parkinsons - - it stops their hands from shaking. Someone mapped which part of the brain is "expecting" pain relief from the placebo effect and found it deep in the middle of the brain, making opiates. We make our own morphine when we think we need to.
Lots of other brilliant stuff on the show too.